From: Michael Wu <michael.wu@kneron.us>
To: Jarkko Nikula <jarkko.nikula@linux.intel.com>,
Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
Mika Westerberg <mika.westerberg@linux.intel.com>,
Jan Dabros <jsd@semihalf.com>,
linux-i2c@vger.kernel.org
Cc: Andi Shyti <andi.shyti@kernel.org>,
Morgan Chang <morgan.chang@kneron.us>,
linux-kernel@vger.kernel.org, Michael Wu <michael.wu@kneron.us>
Subject: [PATCH 0/2] Compute HS HCNT and LCNT based on HW parameters
Date: Wed, 25 Sep 2024 16:04:29 +0800 [thread overview]
Message-ID: <20240925080432.186408-1-michael.wu@kneron.us> (raw)
In commit 35eba185fd1a ("i2c: designware: Calculate SCL timing
parameters for High Speed Mode") hs_hcnt and hs_lcnt are computed based
on fixed tHIGH = 160 and tLOW = 320. However, this fixed values only
applies to the combination of hardware parameters "IC_CAP_LOADING = 400pF"
and "IC_FREQ_OPTIMIZATION = 1". Outside of this combination, SCL frequency
may not reach 3.4 MHz if hs_hcnt and hs_lcnt are both computed using these
two fixed values.
Since there are no any registers controlling these two hardware
parameters, their values can only be noted through the device tree.
Michael Wu (2):
i2c: designware: determine HS tHIGH and tLOW based on HW paramters
dt-bindings: i2c: snps,designware-i2c: add bus-loading and
clk-freq-optimized
.../bindings/i2c/snps,designware-i2c.yaml | 19 +++++++++++++++
drivers/i2c/busses/i2c-designware-common.c | 16 +++++++++++++
drivers/i2c/busses/i2c-designware-core.h | 8 +++++++
drivers/i2c/busses/i2c-designware-master.c | 24 +++++++++++++++++--
drivers/i2c/busses/i2c-designware-platdrv.c | 2 ++
5 files changed, 67 insertions(+), 2 deletions(-)
--
2.43.0
next reply other threads:[~2024-09-25 8:04 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-09-25 8:04 Michael Wu [this message]
2024-09-25 8:04 ` [PATCH 1/2] i2c: designware: determine HS tHIGH and tLOW based on HW paramters Michael Wu
2024-09-25 9:16 ` Andy Shevchenko
2024-09-25 9:21 ` Andy Shevchenko
2024-09-26 8:45 ` Michael Wu
2024-09-26 12:18 ` Andy Shevchenko
2024-09-26 13:50 ` Krzysztof Kozlowski
2024-09-26 14:09 ` Andy Shevchenko
2024-09-25 10:58 ` Jarkko Nikula
2024-09-25 11:02 ` Andy Shevchenko
2024-09-26 9:11 ` Michael Wu
2024-09-25 11:33 ` Krzysztof Kozlowski
2024-09-27 13:41 ` kernel test robot
2024-09-25 8:04 ` [PATCH 2/2] dt-bindings: i2c: snps,designware-i2c: add bus-loading and clk-freq-optimized Michael Wu
2024-09-25 11:32 ` Krzysztof Kozlowski
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20240925080432.186408-1-michael.wu@kneron.us \
--to=michael.wu@kneron.us \
--cc=andi.shyti@kernel.org \
--cc=andriy.shevchenko@linux.intel.com \
--cc=jarkko.nikula@linux.intel.com \
--cc=jsd@semihalf.com \
--cc=linux-i2c@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mika.westerberg@linux.intel.com \
--cc=morgan.chang@kneron.us \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).